Looked into it further and it seems the money will be taken automatically unless I provide a tax number, however my income is quite low and registering to be self employed in the UK would be pointless. Is there anyway to not pay this tax if you don't have an individual tax reference.
Otherwise it seems to me that this is a very expensive toll of business via itch.io
The number has gone up to $250 total that's been held back with a new payout I just initiated and that's a significant amount of money being falsely withheld.